Proteins are typically the key molecule studied as the drug target for drug development generation. High throughput screening of small-molecule and ligand libraries that bind to protein targets is an important part of the process—requiring screening of thousands of small molecules and ligands with a variety of different assays. This screening can require months of time. Protein targets are challenging to work with due to their susceptibility to degradation and aggregation, so protein stability screening is often an important component of lead generation programs. Protein stability screening, performed using the protein melting method, is employed in other research programs that involve native proteins. Protein melting is an extremely useful screening method for the identification of ligands and/or solution (buffer) conditions that maximally stabilize a protein as part of protein purification, crystallization, and functional characterization. The use of fluorescence techniques to monitor protein unfolding is well known to those of ordinary skill in the art. For example, see Eftink, M. R., Biophysical J. 66: 482-501 (1994).
Historically, the methodologies to perform protein melt screening are either very slow and tedious, analyzing one sample at a time—or if high-throughput, require milligram amounts of protein sample and incur high costs in either reagents, or protein samples, or both. It would be useful to have new and useful systems, methods and reagents to screen proteins, including antibodies, to identify ligands, mutations/modifications, buffer conditions, or other factors that affect their melting temperature (Tm) and relative stability.